The World Wide Web (web) is one of the most popular mediums for obtaining information. The increasing popularity of the web has resulted in significant growth in the number of web users and thus an increase in web traffic. The increased traffic causes an increase in the time required for a user to request and receive a webpage. Other causes for increases in the time required for a user to request and receive a webpage are network congestion, low bandwidth, bandwidth underutilization, and propagation delay.
Web development engineers have created hardware solutions in an effort to decrease the time required to request and receive a webpage. One example of a hardware solution is an upgrade for the web servers and bandwidth capabilities. Another hardware solution is the use of a proxy between the user and the web server. In the proxy solution, the proxy has a cache memory for storing webpages that the user frequently visits. The time required to load a webpage from the proxy is significantly less than the time required to load a webpage from the web server. If the proxy does not have the webpage stored in cache memory, then the proxy passes the webpage request onto the web server, and then forwards the user-requested webpage back to the user.
Web development engineers have also developed software solutions in an effort to decrease the time required to request and receive a webpage. One of the software solutions is the concept of prefetching webpages. Prefetching is the process of obtaining webpages from the web server that the user has not yet requested. The main idea in prefetching is to prefetch those webpages that the user will most likely request. The prefetching is preformed during the downtime in the bandwidth, i.e. when the user is not requesting or receiving any webpages.
Many of the prior art versions of prefetching are inefficient in terms of bandwidth consumed and accurately perfecting webpages that the user actually requests. For example, when using a typical web search engine, a user enters search criteria and the search engine displays the ten most relevant responses to the search. The search engine also displays a “next” tag that leads the user to the next ten most relevant responses, and so forth. In some embodiments, after the search engine displays the first ten results, the web browser prefetches the webpages for the displayed links and stores the prefetched webpages in the user's computer. In other embodiments, when the user enters a search, the web browser prefetches the webpages for the links that will be displayed by clicking the “next” link and stores the prefetched webpages in the user's computer. Other embodiments exist where the user can configure the prefetching mechanism to prefetch only specific webpages.
One of the problems associated with the prior art prefetch mechanisms is that the criteria for selecting the particular webpages to prefetch is not very accurate in terms of selecting webpages that the user actually requests. The prior art prefetch mechanisms are also not very bandwidth efficient because a multitude of webpages that are never requested are transmitted to the user's computer. Another problem associated with the prior art prefetch mechanisms is that they must be configured by the user and the configuration process is time consuming and confusing to users who are not very computer savvy. Therefore, a need exists for a more bandwidth efficient prefetching mechanism that more accurately prefetches webpages that the user will likely request and that does not have to be configured by the user.
The prior art has previously addressed the issue of creating improved prefetching mechanisms. For example, U.S. Pat. No. 6,085,226 (the '226 patent) entitled “Method and Apparatus for Utility-Directed Prefetching of Webpages into Local Cache Using Continual Computation and User Models” discloses a prefetch mechanism. The prefetch mechanism in the '226 patent uses a user application, such as MICROSOFT® INTERNET EXPLORER®, to prefetch documents that the '226 invention determines the user might request based on the currently viewed webpage. In the '226 invention, the user can turn on a toolbar in INTERNET EXPLORER® so that when the user visits a webpage, a second webpage is loaded into a frame to the left of the browser. The second webpage shows a list of links to the related pages that are prefetched. The '226 patent could then be used to prefetch those links into the cache memory in the browser. The system prefetches the webpages that the system determines the user will want next. However, the prefetch mechanism in the '226 patent runs on the user's computer and consumes an excessive amount of the critical bandwidth between the user and the proxy. Therefore, a need still exists in the art for a prefetch determination mechanism that limits the usage of the bandwidth between the user and the proxy.
U.S. Pat. No. 6,023,726 (the '726 patent) entitled “User Configurable Prefetch Control System for Enabling User to Prefetch Documents for a Network Server” discloses a prefetch mechanism. The prefetch mechanism in the '726 patent discloses a system that determines the webpages to prefetch. After configuring the prefetching mechanism, the '726 invention uses the prefetch weights in the HTML to determine which webpages to prefetch. Alternatively, the prefetching system can use a pathfile from the server to determine which webpages to prefetch. The prefetch weighting and pathfile generation, as described in the '726 patent, would be the same for every user of the server, i.e. anyone who accesses the server will see the same prefetch results. Thus, the prefetch mechanism in the '726 patent is also unable to provide different prefetching mechanisms for different users. In other words, user A will be given the same prefetched webpages as user B, even though user A's and user B's browsing habits are different. The '726 patent also has the same shortcoming as the '226 patent in that both run on the user's computer. Consequently, a need still exists for a prefetch mechanism that runs on the server side of the web and is able to customize the prefetch mechanism to each individual user.